This proposal requests partial support for the purchase of a 3T whole body MR imaging-spectroscopy system. The hospital and the NMR program will provide the additional funding and long term support for this dedicated research instrument. As part of the MGH-NMR Center, this system will be a resource to the community of PHS-supported biomedical researchers at the MGH managed by the Internal Advisory Committee as outlined by Division of Research Resources in the program announcement. The scope of the MGH-NMR Center, which is largely funded through PHS grants, has expanded to include functional MR imaging and in vivo spectroscopy. Initial studies have enabled the development of novel MR approaches (including functional brain mapping, measurements of oxygen consumption and cell volume fraction as well as receptor and metabolite mapping) that have been applied to important biomedical problems (including alzheimer's and Huntington's Diseases, atheroma, cancer and ischemia) resulting in unique physiological (photic stimulation changes in blood volume to the occipital gray matter) and pathology (elevated lactate in Huntington's Disease) data. While these data are exciting, the capabilities of the available NMR instrumentation do not allow PHS researchers to adequately address new questions resulting from this research. All 14 projects will benefit from the increase in signal-to-noise (improvement in spatial and temporal resolution) provided by the proposed 3.0 T system. Individual projects will be enhanced by increases in spectral resolution and susceptibility contrast. These enhancements are particularly relevant to the susceptibility effects exploited by the brain imaging projects where the functional unit, the column, is just below the spatial resolution set by signal-to-noise at 1.5T. The requested instrument will serve as a hardware and software platform for the development of specialized pulse sequences and data processing to support the growing sophistication of the funded experiments. Through considerable experience in all areas of spectroscopy and functional imaging from theory, to implementation, to clinical applications, the personnel of the MGH-NMR center are well qualified to fully exploit the expanded potentials of the new device. The proposed equipment will be dedicated to research activities and will not be used for routine clinical studies. An award of this high field spectroscopy and imaging instrument will greatly enhance PHS-sponsored work at the MGH.